[YOUTH ENTERTAINMENTS IN THE 1920S USSR] Massovoye deystvo: Rukovodstvo k organizatsii i provedeniyu prazdnovaniya Desyatiletiya Oktyabrya i drugikh revolyutsionnykh prazdnikov [i.e. Mass Actions. Instruction Hot to Organize and Manage Celebration of the 10th Anniversary of October and Other Revolutionary Celebrations]